User Interface Impact Actuator

ABSTRACT

A system generates a haptic effect that simulates a mechanical button. The system receives a signal that indicates that a user has contacted a user interface of the system. The system includes an impact actuator. In response to the signal, a moving element of the impact actuator contacts the user interface, which generates the haptic effect.

FIELD OF THE INVENTION

One embodiment is directed generally to a user interface for a device,and in particular to generating a haptic effect for the user interface.

BACKGROUND INFORMATION

Electronic device manufacturers strive to produce a rich interface forusers. Conventional devices use visual and auditory cues to providefeedback to a user. In some interface devices, kinesthetic feedback(such as active and resistive force feedback) and/or tactile feedback(such as vibration, texture, and heat) is also provided to the user,more generally known collectively as “haptic feedback” or “hapticeffects”. Haptic feedback can provide cues that enhance and simplify theuser interface. Specifically, vibration effects, or vibrotactile hapticeffects, may be useful in providing cues to users of electronic devicesto alert the user to specific events, or provide realistic feedback tocreate greater sensory immersion within a simulated or virtualenvironment.

Haptic feedback has also been increasingly incorporated in portableelectronic devices, such as cellular telephones, personal digitalassistants (PDAs), portable gaming devices, and a variety of otherportable electronic devices. For example, some portable gamingapplications are capable of vibrating in a manner similar to controldevices (e.g., joysticks, etc.) used with larger-scale gaming systemsthat are configured to provide haptic feedback. Additionally, devicessuch as cellular telephones and PDAs are capable of providing variousalerts to users by way of vibrations. For example, a cellular telephonecan alert a user to an incoming telephone call by vibrating. Similarly,a PDA can alert a user to a scheduled calendar item or provide a userwith a reminder for a “to do” list item or calendar appointment.

Increasingly, portable devices are moving away from physical buttons infavor of touchscreen-only user interfaces. This shift allows increasedflexibility, reduced parts count, and reduced dependence on mechanicalbuttons that may be more failure-prone due to moving parts, and is inline with emerging trends in product design. A user of a touchscreen orother types of user interface may still desire the familiar touch andfeel of mechanical buttons. However, different requirements exist forthe haptic actuator for the creation of haptic effects for touchconfirmation as opposed to general alerts and ringtones.

SUMMARY OF THE INVENTION

One embodiment is a system that generates a haptic effect that simulatesa mechanical button. The system receives a signal that indicates that auser has contacted a user interface of the system. The system includesan impact actuator. In response to the signal, a moving element of theimpact actuator contacts the user interface, which generates the hapticeffect.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of a handheld device in accordance with oneembodiment.

FIG. 2 is a generalized block diagram of an interaction of an impactactuator and a touchscreen in accordance with one embodiment.

FIG. 3 is a cross-sectional view of the device in accordance with oneembodiment.

FIG. 4 is a flow diagram of the functionality performed by the device ofFIG. 1 in accordance with one embodiment in order to create hapticeffects that simulate a mechanical button.

DETAILED DESCRIPTION

One embodiment is a device with a user interface. The device includes anactuator that intermittingly contacts the user interface to create ahaptic effect that substantially duplicates the touch and feel of amechanical button.

FIG. 1 is a block diagram of a handheld device 10 in accordance with oneembodiment. Device 10 includes a touchscreen 11 or other type of userinterface, and may include mechanical keys/buttons 13. Internal todevice 10 is a haptic feedback system that generates vibrations ondevice 10. In one embodiment, the vibrations are generated ontouchscreen 11.

The haptic feedback system includes a processor 12. Coupled to processor12 is a memory 20 and an actuator drive circuit 16, which is coupled toan impact actuator 18. Processor 12 may be any type of general purposeprocessor, or could be a processor specifically designed to providehaptic effects, such as an application-specific integrated circuit(“ASIC”). Processor 12 may be the same processor that operates theentire device 10, or may be a separate processor. Processor 12 candecide what haptic effects are to be played and the order in which theeffects are played based on high level parameters. In general, the highlevel parameters that define a particular haptic effect includemagnitude, frequency and duration. Low level parameters such asstreaming motor commands could also be used to determine a particularhaptic effect. A haptic effect may be considered “dynamic” if itincludes some variation of these parameters when the haptic effect isgenerated or a variation of these parameters based on a user'sinteraction.

Processor 12 outputs the control signals to drive circuit 16 whichincludes electronic components and circuitry used to supply impactactuator 18 with the required electrical current and voltage to causethe desired haptic effects. Impact actuator 18 is a haptic device thatgenerates a vibration on device 10. Impact actuator 18, disclosed inmore detail below, can generate a haptic effect having a relatively highfrequency and low peak-to-peak acceleration in order to better simulatea mechanical button. Memory device 20 can be any type of storage deviceor computer-readable medium, such as random access memory (“RAM”) orread-only memory (“ROM”). Memory 20 stores instructions executed byprocessor 12. Memory 20 may also be located internal to processor 12, orany combination of internal and external memory.

Touchscreen 11 recognizes touches, and may also recognize the positionand magnitude of touches on a touch sensitive surface. The datacorresponding to the touches is sent to processor 12, or anotherprocessor within device 10, and processor 12 interprets the touches andin response generates haptic effect signals. Touchscreen 11 may sensetouches using any sensing technology, including capacitive sensing,resistive sensing, surface acoustic wave sensing, pressure sensing,optical sensing, etc. Touchscreen 11 may sense multi-touch contacts andmay be capable of distinguishing multiple touches that occur at the sametime. Touchscreen 11 may further display images for the user to interactwith, such as keys, dials, etc., or may be a touchpad with minimal or noimages.

Although the embodiment of FIG. 1 is a handheld device, otherembodiments may be any type of device that provides a user interface andincludes a haptic effect system that includes an impact actuator. Theuser interface can be a touchscreen, or can be any other type of userinterface such as a mouse, touchpad, mini-joystick, scroll wheel,trackball, etc.

User interfaces formed from mechanical buttons provide a naturallyoccurring feedback to a user. In general, the feedback provided by mostmechanical keys is in the form of a single cycle sine wave that includesone up cycle and one down cycle. Some known devices use haptic effectsto duplicate the feel of mechanical buttons for other user interfacessuch as touchscreens. These known devices typically use actuators toapply a vibrotactile force. The actuators typically used in thesedevices are Eccentric Rotating Mass (“ERM”) actuators, in which aneccentric mass is moved by a motor, or Linear Resonant Actuators(“LRA”s), in which a mass attached to a spring is driven back and forth.However, the vibration effects generated by these actuators in somecases include multiple cycles so they do not do a credible job ofsimulating mechanical buttons that have a single cycle. Further, thesetype of actuators typically are not able to easily fit into touchscreendevices that continuously get smaller in size.

FIG. 2 is a generalized block diagram of an interaction of the impactactuator and touchscreen 11 in accordance with one embodiment. A portionof the impact actuator, referred to as a “moving element” 24, contactstouchscreen 11 when an input driving pulse 20 is applied to generate amechanical impact between moving element 24 and touchscreen 11. In oneembodiment, the contact is intermittent in that moving element 24strikes touchscreen 11 and immediately moves away from touchscreen 11.In another embodiment, the contact can be long term in that movingelement 24 strikes touchscreen 11 and remains in contact for apredetermined duration of time. In this embodiment, the sustainedcontact between moving element 24 and touchscreen 11 quickly dampens outthe vibrations. In either embodiment, a vibration waveform 22 thatresults from the contact is formed substantially of a single waveformthat quickly dissipates so that the vibration more realisticallysimulates a mechanical button.

FIG. 3 is a cross-sectional view of device 10 in accordance with oneembodiment. Device 10 includes touchscreen 11 which is coupled andgrounded to a housing 32. The impact actuator includes a piezo bender 34coupled to housing 32 and a rubber mallet 36 coupled to bender 34. Inoperation, when a pulse signal is applied to piezo bender 34, it curlsup and rubber mallet 36, a moving element, strikes or contactstouchscreen 11. As in FIG. 2, the contact can be intermittent or of alonger duration to dampen vibrations. In another embodiment, piezobender 34 itself is the moving element that contacts touchscreen 11, andrubber mallet 36 is not needed.

Impact actuator 18 in accordance with embodiments of the invention hasthe following advantages over known actuators that allow it to bettersimulate a mechanical button or key: (1) It generates faster hapticeffects due to the impact nature of the response; (2) It generates arelatively crisp effect due to the nature of the impact frequency; (3)It is adapted for pulse driving so that the actuator does not drive theuser interface in a continuous vibration; (4) It is adaptable to besmaller in size because in some embodiments it could be in the form of astrip (e.g., a piezo bender), a small cube (e.g., a stack piezo), or apin (e.g., a coil with shaft). This allows it to be fit into smallerplaces and enable applications like thin cellular telephones.

In another embodiment, impact actuator 18 is implemented by a relay thatincludes a coil plus a moving part that strikes the user interface andincludes a spring return. In another embodiment, a shape memory alloy(“SMA”) in a relay configuration is used, a direct current (“DC”) motorhaving an arm as the moving element is used, or actuator 18 can be anElectroactive Polymer.

FIG. 4 is a flow diagram of the functionality performed by device 10 ofFIG. 1 in accordance with one embodiment in order to create hapticeffects that simulate a mechanical button. In one embodiment, thefunctionality of FIG. 4 can be performed by any combination of hardwareand software.

At 402, the user contacts the user interface. The user interface may bea touchscreen or any other type of user interface.

At 404, the contact at 402 generates a signal that is received byprocessor 12. In response, processor 12 generates a haptic effectsignal. In one embodiment, the haptic effect signal includes a drivingpulse that is applied to impact actuator 18.

At 406, in response to the haptic effect signal, the moving element ofimpact actuator 18 contacts the user interface. The contact may beintermittent or last for a predetermined duration.

As disclosed, in one embodiment a device includes a user interface withan impact actuator that has a moving element. The moving elementcontacts the user interface in response to a user contacting the userinterface. The haptic effect that results from the contact by the movingelement is similar to the touch and feel of a mechanical button.

Several embodiments are specifically illustrated and/or describedherein. However, it will be appreciated that modifications andvariations of the disclosed embodiments are covered by the aboveteachings and within the purview of the appended claims withoutdeparting from the spirit and intended scope of the invention.

1. A method of generating a haptic effect comprising: receiving a firstsignal that indicates that a user has contacted a user interface; and inresponse to the first signal, contacting the user interface with amoving element of an actuator.
 2. The method of claim 1, wherein theuser interface is a touchscreen.
 3. The method of claim 1, furthercomprising generating a haptic effect signal that is applied to theactuator.
 4. The method of claim 1, wherein the haptic effect signalcomprises a driving pulse.
 5. The method of claim 1, wherein theactuator comprises a piezo bender.
 6. The method of claim 5, wherein themoving element is a rubber mallet coupled to the piezo bender.
 7. Themethod of claim 1, wherein the contacting is intermittent.
 8. The methodof claim 1, wherein the contacting is for a predetermined time duration.9. A device comprising: a user interface; a processor coupled to theuser interface; and an actuator coupled to the processor, wherein theactuator comprises a moving element that is adapted to contact the userinterface when the actuator receives a haptic effect signal from theprocessor.
 10. The device of claim 9, wherein the user interface is atouchscreen.
 11. The device of claim 9, wherein the haptic effect signalcomprises a driving pulse.
 12. The device of claim 9, wherein theactuator comprises a piezo bender.
 13. The device of claim 12, whereinthe moving element is a rubber mallet coupled to the piezo bender. 14.The device of claim 9, wherein the contact is intermittent.
 15. Thedevice of claim 9, wherein the contact is for a predetermined timeduration.
 16. The device of claim 9, wherein the actuator comprises arelay.
 17. The device of claim 9, wherein the actuator comprises a shapememory alloy.
 18. The device of claim 9, wherein the actuator comprisesa direct current motor having an arm.
 19. An impact actuator comprising:a piezo bender; and a rubber mallet coupled to the piezo bender.
 20. Amethod of generating a haptic effect comprising: receiving a firstsignal that indicates that a user has initiated a function via a userinterface; and in response to the first signal, contacting the userinterface with a moving element of an actuator.
 21. The method of claim20, wherein the user interface is a touchscreen and the function isinitiated by contacting the touchscreen.
 22. The method of claim 20,wherein the user interface is a mouse and the function is initiated bymoving the mouse.
 23. The method of claim 20, wherein the user interfaceis a joystick and the function is initiated by moving the joystick.